Process of cleaning porcelain surfaces



United States Patent 3 382 182 PROCESS OF CLEANING PORCELAIN SURFACES John R. Moyer, Midland, Micln, assignor to The Dow Chemical Company, Midland, Mich., a corporation of Delaware No Drawing. Filed Oct. 4, 1965, Ser. No. 492,934

r 3 Claims. (Cl. 252-186) ABSTRACT OF THE DISCLOSURE White porcelain sink facilities are very prevalent in normal household and other kitchens. Accordingly, when aluminum cookware is washed in these sinks, the sink becomes marked or stained due to the rubbing off of aluminum metal from the cookware on, e.g., the walls and bottom of the sink. Such marks are quite resistant to chemical attack, especially white porcelain sinks which have had extended use, and therefore have heretofore been removed mostly by scouring or some other mechanical means. Moreover, scouring a sink in this manner tends to aggravate the cleaning problem thereof since it wears off the initial glaze of the porcelain making it more porous and susceptible to permanent staining. Therefore, a cleaner which would chemically remove aluminum and other similar marks in a rapid manner without the use of an abrasive, or, without the degree of effort heretofore required when an abrasive is used would be highly desirable.

The principal object of the present invention is to provide a new and novel chemical cleaner for primarily chemically removing metal marks from porcelain surfaces and the like.

Another object of the invention is to provide a chemical cleaner composition particularly useful in removing aluminum marks from the surfaces of porcelain sinks and the like.

It has been found in accordance with the present invention that the aforesaid stains and marks can be removed by moist contact with a metal peroxide cleaning agent, such as, e.g., calcium peroxide, either with or without scrubbing. As aids in promoting removal of these marks and stains a surfactant and/ or an abrasive for mild scouring may, as optional additional ingredients, also be employed. Though removal of the aforesaid stains and marks is readily accomplished by contact with the essentially pure peroxide cleaner alone, it is contemplated and preferred for convenience and economy of materials that the peroxide be employed in a dilute cleaning composition together with the surfactant and a diluent material as a filler or abrasive.

Accordingly, the present invention comprises in practice a dry free flowing chemical cleaning composition consisting essentially of from about 1 to about 6 weight percent of an alkaline earth metal peroxide as a chemical cleaning agent, and from about 0.5 to about 5.0 weight percent of a surfactant, such as, e.g., a commercial detergent, the balance being a bulk diluent serving either as an inert filler, or as an abrasive substance for scouring.

3,382,182. Patented May 7, 1968 Preferably, the present novel cleaning composition will contain about 1 percent of the alkaline earth metal peroxide, calcium peroxide being preferred, and from about 2 to 3 percent of a detergent, the balance being a finely divided abrasive.

Alkali metal peroxides, such as e.g., sodium peroxide, and lithium peroxide may also be used as the metal. peroxide of the present invention with excellent results, particularly sodium peroxide. The alkaline earth metal peroxides, however, are preferred since they are much more stable and are thus superior for use in a dry, free flowing, stable cleaning composition. Examples of alkaline earth metal peroxides which may be used include: calcium peroxide, barium peroxide, and strontium peroxide.

The term metal peroxide as used herein includes the alkali metal and alkaline earth metal peroxides.

The detergent material used in the present composition may be any compatible commercial cationic, anionic or nonionic detergent or surfactant. This material when moistened or contacted with water aids in the cleaning of the stains or marks in the normal manner. Examples of classes of these materials include: quarternary alkyl ammonium salts, alkylaryl sulfonates, amine oxides and amides.

Abrasives which may be used, either singly or in combination, as a scouring agent in the present novel cleaning composition may be any abrasive in a very finely divided, powder-form, which is compatible with and nondetrimental to the user and to the surface desired to be cleaned. An example of a suitable and common abrasive includes ground crystalline mica, or finely divided pumice.

The above novel cleaning composition cleans, e.g., the aforesaid aluminum marks from sinks, with or without scouring, in a rapid, eflicient and convenient manner. The composition is dry, free flowing, and is reasonably stable as to peroxygen value. It employs commonly available ingredients, is easy to prepare, and is effective in its action to remove or minimize metal stains, marks, and the like, such as aluminum marks.

The following examples serve to further illustrate the present cleaning composition but are not to be construed as limiting the invention thereto:

EXAMPLE I Aluminum stains and marks were applied generously to the surface of a white porcelain sink by rubbing it actively with a crumpled ball of commercial household aluminum foil. The sink was one which had been used a number of years, thus had the glaze worn off somewhat. Separate portions of the stained area were treated as follows:

(1) A commercial household cleanser containing a chlorine bleach, a surfactant and an abrasive was contacted with the wetted portion of the sink so marked. N0 scouring or rubbing was employed.

(2) A composition containing 3 percent of CaO and 97 percent of an abrasive was contacted with another portion of the sink as in (1). No scouring or rubbing was employed.

(3) Water only was applied to the on still another portion of the sink.

After about 2 minutes, all portions were rinsed off with an excess of water. Portions (l) and (3) remained badly stained and marked. Portion (2) was substantially stain and mark-free. The composition containing the calcium peroxide was manifestly superior in removing the aluminum marks.

marks with rubbing EXAMPLE II A cleaning composition in accordance with the present invention comprising 1 percent CaO and 99 percent of an abrasive filler of calcium carbonate was prepared and applied generously to a wetted portion of a white porce- 3 lain sink which had been marked up with aluminum foil as in Example 1. After 5 minutes standing, the sink was flushed with water. The aluminum marks were all removed.

EXAMPLE III The procedure of Example 11 was repeated except that the composition comprised about 2.5 percent of C210 and 97.5 percent of the abrasive. Again the marks were rapidly and effectively removed.

EXAMPLE IV A composition as in Example II was prepared and similarly applied to an aluminum marked sink, except that the composition contained about 6 percent CaO No scrubbing was employed. After about 2 minutes the sink was rinsed with water. The aluminum marks were very effectively all removed.

EXAMPLE V Various compositions were prepared and tested as in Example II above, except that Na O SrO and BaO were used instead of calcium peroxide. In each case the aluminum marks were effectively removed, especially in the case of sodium peroxide.

Other compositions in accordance with the present invention varying as to amount and kinds of metal peroxides, detergents, and abrasives, may be also prepared and employed to remove various type stains and/ or marks from porcelain sinks.

The present invention may be modified or changed without departing from the spirit or scope thereof, and it is 4 understood that the invention is only limited as defined in the accompanying claims.

I claim:

1. A method of removing aluminum stains and marks from a porcelain surface which comprises: applying to said stained and marked surface a cleaning composition in moist contact therewith, said composition as the active ingredient consisting essentially of a metal peroxide selected from the group consisting of alkali metal and alkaline earth metal peroxide, continuing moist contact of the cleaning composition with said porcelain surface for a period of time sufficient to eliminate said stains and marks, and removing said cleaning composition from said porcelain surface, thereby removing aluminum stains and marks therefrom.

2. The method of claim 1 wherein the cleaning composiiion consisting essentially of from about 1 to about 6 Weight percent of said metal peroxide.

3. The method of claim 1 wherein the metal peroxide is calcium peroxide.

References Cited UNITED STATES PATENTS 2,005,448 6/1935 Aisen 252186 2,037,566 4/1936 Durgin 252-186 X 3,048,546 8/1962 Lake et al 252 95 MURRAY KATZ, Primary Examiner.

LEON D. ROSDOL, Examiner.

M. WEINBLATT, Assistant Examiner. 

